Electric furnace.



Patented Feb.3,`1914..

B. GUTHRIE & J. P. KARGH.

ELECTRIC FURNACB.

APPLIUATION FILED JUNEZQ, 1912.

FIG.

INVENTOR. rfi f vg. I feud.

WITNESSES.

B. GUTHRTE 1 J. P. KARGH.

ELECTRIC FURNAGE.

APPLICA'rIon FILED m1111129, 1912.

Patented Feb. 3, 1914.

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man@ @um UNITED STATES PATENT oFFroE, i

BAYARD GUTHRIE, 0F PTTSBURGH, AND J OSEPH PKARCH, OF SEWICKLEY, PENN- SYLVANIA, ASSIGNORS T0 C. P. CARPENTER, TRUSTEE, OF PITTSBURGH, PENNSYL- VANIA.

Application led June 29. 1912.

ticularly concerned with improved apparatus tor this purpose.

The invention constitutes an improvement over that. described in Letters Patent ot the United States No. 979,663, more particularly with a view to producing an apparatus better suited for operation with a direct current or single phase alternating current where quarter phase current is not available. y

'l`he'invention has further for its object to provide improved means for mounting a mold in constant relation to the outlet of the crucible of the `furnace whereby the metal discharged from the said outlet will tlow directly to the center of the bottom of said mold without in its, assage contacting with the sides of. the mold? In the accompanying drawings Figure 1 is a plan view in partial horizontal section ot an apparatus embodyingl our invention. Fig. 2 is a vertical section showing the mold and the support in elevation.' Fig. 3 is a sectional view at' right angles to that shown 1n Fig. 2.

' view. Fig. 5 is a sectional view on the line 5v5l4`ig. 3. Fig. 6 is a detail of the steady plates for the carrying bars of one of the electrodes; and Fig. 7 1sl a rear view of one of the electrodes showing the connected terminal for the electric circuit in conjunction therewith.

In the embodiment of ourinvention herein selected for illustration, 1 indicates the furnace casing which may be provided with a, bottom plate 2 pivotally secured thereto and a removable cover plate 3 having an opening t to afford access to the Crucible .5 that opening being provided-with a movable cover '6. The casing may be and pref- Specification of Letters Patent.

Fig. 4 is a horizontal sectionaly ELECTRIC FURNACE.

Patented Feb. 3, 1914. serial No. 706,596.

erably is of substantially cylindrical section and is preferably cast either with the lugs or trunnion bases 7. 7 to which cylindrical trunnions 8, 8 may be secured. These trunnions 8 may be mounted in suitable standards or brackets such as illustrated in Patent No. 979,663, above referred to and any desired means for tilting the furnace such, for example as that illustrated in said patent, may be provided. The crucible 5 which may be'of suitable refractory coinpositiomisuch for example as plumbago,

clay and sand, is supported within the casing by one or more layers 9 of tire brick or other refractory material whereby it is thoroughly insulated from the-bottom plate ot the casing and is surrounded by a wall 10 of fire brick extending practically to the top of the casing, but so arranged as to leave between itself and the Crucible a chamber or pair of chambers 11 separated from each other by refractorypartitions 12--12, Figs. l and 4. These partitions at their inner edges conform closely to and fit snugly against the side of the Crucible. .'lVithin the lateral chambers 11. 11 are mounted the electrodes 13, 13, which as here. shown are in the form of substantially semi-conical body portions of reduced diameter at the bottom to tit snugly against the lower portion of the Crucible wall and flaring at the top toprovide spaces 14, 14 around the Crucible which may be lled with broken carbon for 'the purpose of furnishing resistance to b ieak up and make a more even distribution of the electric arc over the surface of the cnicible. his carbon may be fed into the space through suitable holes 3 in the cover plate 3. Each of the carbon electrodes 13 is provided preferably with a fastening lug orfjstem 13' preferably bolted into the copper elect-rode holders 15, 15,`which in turn are provided with the portions 15 having terminal sockets 15 for the usual connection 1with the terminals of the cables carrying the current. The electrode holders 15 are carried by suitable carrying ba s 16 bolted to and manip# ulated from sai holders, these carrying bars passing through slots 17, 17 (Fig. 6) of a steady plate or disk 18 of circular form to fit- Within the hollow trunnions 8. These steady plates are each provided with oppograduaiiy reducs the intensity :is baffits i'iiimio 'rfi Y "vided, with. ings Qi vraie/mbk; mi ne eter at right angles i0 the ings 19 by which each steady plate .o1` disk is heid tation,- 01* rocking iipon its set Each .plate is also j 1 ied'witii opening ahioi ing Sie simian* Tin against r0- S WS 20.

angle' and Q3- 'ii may umec Y this naamw the all tim pre-pai posoii to, 'scei'e and iii -y hold the Crucible ai: botom shown in Fifa. 3.

reason he ceiiacjing '.owef edges of the elecfmes: 'with the boztom off th crue-foie ich@ ive gene@ ,of die @iev troes upwar ,ly away frsm the ciucmie, he heang effects ius i@ the aciiig acm-)ss of the eiectredes t@ the cruaibie is mote ii tense at the top than at the bottoni, ancitom is reached. Thus ,he molen melia! at tha tap of 'the (frucibia ti'iciies down dimi the. 'unmcited 1112x539 'the bottom of ifi e cwi-- cible whereby it n'iaintaiis the prsp@ of the molten mass. The broken car tel'posi between iii@ ,iucibie and t trades serves To u'mif up the az'ciii and .distribute if, more evenly over th face of' the C'iiciboi aziv thm pieveng eating muy of the ucibie .at any pa''cni point "01' points. The 'portion o?? fha bljick Qrivnroduced the auf ti'bdes prevents :uciig trod t the other and 'ofthe icl to, and 4 of izhe'eiectrod'g "biieffeib util the u @i feet 0i he, culriev 'Qr' @he Iemiciozi pm@ n 'this form 'of ppiiiatus, morovi', but two eie0ti'ocie`s` are' cmpioyed direced. t@ opposie points oi'fey cliieoie,"siieire`i3y rendering the, device pairticuimiy adapted foi Qpiation Withdiiecft cuiint or single phase Miei; iii" ing' uirc'nt. The fui-.mme `is provided W: a suitable spout 'iiviiigiiiiared inne? @mi 30 adapted to jclcaSelyiibout the upper edge of the cyci'b'i iiving' a iip 8l t@ insure the ivectiig of the molt-en cont-ents '(fiiie Spiu'n. The, spout of th crucibie' projects soms i. une bey-sind the @aber 35i Wifi" a Y l A1; 'H :50 @253 Hymn Live upper ed@ @i said ii` -j rings. iie hooks 32 am so positioned i tively izo he outer Gnd of the Spmi that the` Spc@ Wiii` im'guiuhilx li Merge ti :ia Tuffi?) f diicuii ie ci:

hdd by 'mc-1i we "gf ai herein (i ticuim" en'ibodiiiiezi; of om' V'i be uiidcswod within the scope Ve claiml. An eiecti'ic cibl, pmi? of and Sc; located fine-half of said justingg .Quid @im crucibie.

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l: J TOO Cibi@ ai, *ghe wird thv "01mm (hermine til@ t-hfl thc- Sfiii'ie muy be iii detaiis, and iii m'izmgemei'its of psf-.its

@dos mi, arca oi the i coiii'ficiiiig); 'wiii *iw l mios nach @surprising :i cru-- amzxiiged upon op @wird and from said Crucible vbroken carb 't-ifids; and

ci' u ci iii furnace umiipiising a. @rug electrodes @zich of a simpa :is to 1.110102@ siiilisiziiitifliiw @sa-riied :i paii wantiony it im ed claims.

ci: mffiussinf.

u ci

the Crucible,

to adj usf: said ther removed areasof said Crucible, meansfor adjustingl a. refractory and non-Conductinglining, a

Crucible mounted within said lining, said; lining haring portions contacting with opposite sides of said Crucible forming Chambers upon opposite sides vof the Crucible separated from each other by said lining, electrodes within said Chambers separated from each other by said lining and adaptedto be adjusted toward and from said Crucible.

7. In an electric furnace, a Casin having a refractory and non-conducting ining, a Crucible mounted within said lining, said lining having portions contacting with opposite sides of said Crucible forming Chain bers upon oppositcsi des of the Crucible, electrodes within said chambers separated from each other by said lining, the lower portions of said electrodes Contacting with said Crucible and the upper portions diverginzi,r therefrom to increase the heating effect on said Crucible from the bottom to the top.

8. In an electric furnace, a Casing havinga refractory and non-Conducting lining, a Crucible mounted within said lining, said lining having` portions contacting with opposite sides of said Crucible forming Chambers upon. opposite sides of the Crucible, electrodes within said chambers separat/ed from each other' by said lining, the lower portions of said electrodes contacting with said Cru- Ciblel and the upper portions diverging therefrom to increase the heating effect on said Cru ible from the bOttom to the top, and a resistance element interposed between said electrodes and said Crucible.

9. In an electric furnace, a Crucible, a pair of electrodes adjacent thereto, a bridge wall -of refractory non-conducting material separating said lelectrodes so that the heat generated may be deflected to or Concentrated in said Crucible.

10. In an electric furnace, thecombination. of a. tiltable Casingl having a lining of lire-brick, said lining having a dividing wall forming` chambers upon opposite .sides of said Crucible, opposite electrodes in said chambers inclosing comparatively large said electrodes whereby they may be :in Contact with said Crucible and position the same within said furnace.

11. In an electric furnace, the Combination with a tiltable casing havinga'lining of tire-brick forming a division Wall in the furnace, opposite electrodes adjacent said" :Crucible and adapted in conjunction-with said division wall to hold and support said Crucible when pouring.

12. In an electric furnace, the Combination with -a tiltablev casing', of a, refractory liningr therefor, a Crucible inclosed within said lining, said 'lining-havingj a' dividing wall forming chambers upon opposlte sides of said Crucible, electrodesin sind opposite chambers shaped to contact with the lower portion of said Crucible and diverging from the upper portion thereof, a resistance element interposed between said elect-redes and said Crucible, said division vgall being adapted to-hold and support said Crucible when pouring.

13. In an electric furnace, the Combination with a tiltable casing, of a refractory lining,r therefor, a Crucible inelosed Within said lining, said lining having a dividing wall forming chambers upon opposite sides of said Crucible, electrodes-in said opposite Chambers shaped to Contact with the lower portion of said Crucible and diverging from the upper portion thereof, a resistance element interposed between said electrodes and said Crucible, a spout leading from said Crucible tothe exterior of said furnace, said division wall heilig adapted to hold and support said vCrucible when pourinv'.

14. In an electric furnace, the Combination with a tiltable casing, of a refractory lining therefor, a Crucible inclosed within said lining, said lining having a dividing wall forming chambers upon opposite sides of said Crucible, electrodes vin said opposite Chambers shaped to Contact with the lower portion of said Crucible and diverging from the upper portion thereof, a vresistance element interposed between said electrodes and said Crucible, a spout leading from said Crucible to the exterior of said furnace, said division wall being adapted to hold and supsaid Crucible, a spout leading from said Cru- Cible tothe exterior of said furnace, said division wall being` adapted to hold and support said Crucible when pouring, a mold swingingly supported on said furnace on an axis passingy through the end' of said spout.

v1-6. In an electric furnace, the Combination with a tiltable Casing, ofI a refractory .lining therefor, a Crucible inclosed within ,said lining, said lining having a dividing wall forming chambers upon opposite 'sides of said Crucible, electrodes in said opposite Chambers shaped to Contact withthe lower portion 'of said'crucible and diverging from the upper portion thereof, a resistance element interposed between said electrodes and said Crucible, a spout leading from said 

